249731 has 4 divisors (see below), whose sum is σ = 255864. Its totient is φ = 243600.

The previous prime is 249727. The next prime is 249737. The reversal of 249731 is 137942.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 249731 - 2² = 249727 is a prime.

It is a super-2 number, since 2×249731² = 124731144722, which contains 22 as substring.

It is a Duffinian number.

It is a zygodrome in base 2.

It is a self number, because there is not a number n which added to its sum of digits gives 249731.

It is not an unprimeable number, because it can be changed into a prime (249737) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3005 + ... + 3086.

It is an arithmetic number, because the mean of its divisors is an integer number (63966).

2²⁴⁹⁷³¹ is an apocalyptic number.

249731 is a deficient number, since it is larger than the sum of its proper divisors (6133).

249731 is an equidigital number, since it uses as much as digits as its factorization.

249731 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6132.

The product of its digits is 1512, while the sum is 26.

The square root of 249731 is about 499.7309276000. The cubic root of 249731 is about 62.9734498018.

The spelling of 249731 in words is "two hundred forty-nine thousand, seven hundred thirty-one".